1. Technical Field
The present invention generally relates to a serial bus interfaces and in particular to signals of serial bus interfaces.
2. Description of the Related Art
In a serial interface, such as an inter-integrated circuit (I2C) interface, occasionally conditions arise whereby a master device or a target device hold on to one or both signals within the serial interface. Multiple methods have been attempted to solve the problem of signal holds, or freeing the serial bus of hang conditions.
A first method utilized for freeing the serial bus of hang conditions comprises issuing a particular number of clocks with a data signal at a high. Issuing the number of clocks is not a successful method for freeing the serial bus of hang conditions. The clocks and data signals may be held low by a failing device, and the master may not be capable of driving the clocks and/or data. Another problem with the method of issuing a number of clocks with a data signal at a high state is simply driving clocks with data held at a certain state may cause erroneous data to be written to a targeted device given the operation held on the serial bus is a write at the time of the failure. An alternative method utilized for freeing a serial bus of hang conditions is for the supervising device to issue a reset signal to all devices attached to the bus; however, not all devices implement a dedicated reset input for such purposes.